MARK 1

Split Data into 1 year

Isolation Forest

Plot all of the data with this code:

Isolation Forest

WORKING CODE:

STOP AND BREATHE

STOP AND BREATHE

STOP AND BREATHE

Mark II
Mark III

Isolation forests are an unsupervised extension of the popular random forest algorithm. The building blocks of isolation forests are isolation trees with a binary outcome (is/is not an outlier).

When an isolation forest is built, the algorithm splits each individual data point off from all other data points. The easier it is to isolate a single point in space from all other points, the more likely it is an outlier (because it’s far away from all other data points). If a data point is an in-lier, it will be closely surrounded by other data points, and will take more splits to isolate (1). See the graphic below as an illustration.

Mark III
Mark IV

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